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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-ia64/semaphore.h
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Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-ia64/semaphore.h')
-rw-r--r--include/asm-ia64/semaphore.h102
1 files changed, 102 insertions, 0 deletions
diff --git a/include/asm-ia64/semaphore.h b/include/asm-ia64/semaphore.h
new file mode 100644
index 000000000000..3a2f0f3f78f3
--- /dev/null
+++ b/include/asm-ia64/semaphore.h
@@ -0,0 +1,102 @@
+#ifndef _ASM_IA64_SEMAPHORE_H
+#define _ASM_IA64_SEMAPHORE_H
+
+/*
+ * Copyright (C) 1998-2000 Hewlett-Packard Co
+ * Copyright (C) 1998-2000 David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+
+#include <linux/wait.h>
+#include <linux/rwsem.h>
+
+#include <asm/atomic.h>
+
+struct semaphore {
+ atomic_t count;
+ int sleepers;
+ wait_queue_head_t wait;
+};
+
+#define __SEMAPHORE_INITIALIZER(name, n) \
+{ \
+ .count = ATOMIC_INIT(n), \
+ .sleepers = 0, \
+ .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
+}
+
+#define __MUTEX_INITIALIZER(name) __SEMAPHORE_INITIALIZER(name,1)
+
+#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
+ struct semaphore name = __SEMAPHORE_INITIALIZER(name, count)
+
+#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1)
+#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name, 0)
+
+static inline void
+sema_init (struct semaphore *sem, int val)
+{
+ *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val);
+}
+
+static inline void
+init_MUTEX (struct semaphore *sem)
+{
+ sema_init(sem, 1);
+}
+
+static inline void
+init_MUTEX_LOCKED (struct semaphore *sem)
+{
+ sema_init(sem, 0);
+}
+
+extern void __down (struct semaphore * sem);
+extern int __down_interruptible (struct semaphore * sem);
+extern int __down_trylock (struct semaphore * sem);
+extern void __up (struct semaphore * sem);
+
+/*
+ * Atomically decrement the semaphore's count. If it goes negative,
+ * block the calling thread in the TASK_UNINTERRUPTIBLE state.
+ */
+static inline void
+down (struct semaphore *sem)
+{
+ might_sleep();
+ if (atomic_dec_return(&sem->count) < 0)
+ __down(sem);
+}
+
+/*
+ * Atomically decrement the semaphore's count. If it goes negative,
+ * block the calling thread in the TASK_INTERRUPTIBLE state.
+ */
+static inline int
+down_interruptible (struct semaphore * sem)
+{
+ int ret = 0;
+
+ might_sleep();
+ if (atomic_dec_return(&sem->count) < 0)
+ ret = __down_interruptible(sem);
+ return ret;
+}
+
+static inline int
+down_trylock (struct semaphore *sem)
+{
+ int ret = 0;
+
+ if (atomic_dec_return(&sem->count) < 0)
+ ret = __down_trylock(sem);
+ return ret;
+}
+
+static inline void
+up (struct semaphore * sem)
+{
+ if (atomic_inc_return(&sem->count) <= 0)
+ __up(sem);
+}
+
+#endif /* _ASM_IA64_SEMAPHORE_H */
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